Opposition activists and supporters take part an anti-Putin protest in central in Moscow, on September 15, 2012. Thousands marched today through Moscow to protest against the rule of Vladimir Putin in a test of the opposition's challenge to the Russian president four months after his inauguration. It was also the first mass action since the sentencing of three members of Pussy Riot to two years in prison for an anti-Putin protest in an Orthodox cathedral, which has become a rallying cause for many in the opposition.